Blank for making fibre container



June 16, 1964 E. M. cRoUsE ETAL 3,137,431

yBLANK FOR MAKING FIBRE CONTAINER Filed Nov. 19, 1962 3 137 431 BLANK FoR MAKING FIBRE CONTAINER Earl Myron Crouse and Harold Ernest Spaulding, Palmer Township, Easton, Pa., assignors to American Can Company, New York, N.Y., a corporation of New Jersey Filed Nov. 19, 1962, Ser. No. 238,609 7 Claims. (Cl. 229-15) This invention relates to a disposable, tapered, nestable container whose body is formed from a single libre blank, and has particular reference to such a container whose transverse cross-section is substantially rectangular.

In the past, many and various types of conical nestable containers have been developed; but one objection to such containers is that considerable space is taken up by the container in both storage and shipping, due to its transverse circular configuration. The preference for circular or conical shaped containers has been principally due to their amenability to high-speed forming methods, whereas tapered, nestable, libre containers with rectangular crosssections have not lent themselves to such high-speed production techniques.

The present invention has overcome these production diiiiculties, while still retaining a simplicity in construction comparable to the conventional truncated conical fibre container.

An object of the present invention is to provide a disposable, tapered, nestable, libre container having a substantially rectangular transverse cross-section.Y

Another object is to provide a blank for forming a tapered, nestable, libre container body having a polygonal transverse cross-section.

An additional object is to provide a fibre blank which, upon being formed into a tapered, nestable container body, results in the body having the shape of a truncated substantially rectangular pyramid.

A still further object is to provide such a container having a longer perimeter at the top than at the bottom and provided with a brim at the top.

Yet a further object is to provide a rectangular, nestable container wherein the container brim lies in a substantially single plane.

A further object is to provide such a container which is amenable to high-speed container forming operations.

Numerous other objects and advantages of the invention will be apparent as it is better understood from the following description, which, taken in connection with the accompanying drawings, discloses a preferred embodiment thereof.

The above objects are accomplished by providing a libre sheet or blank havingside edges and a leading and trailing edge extending between the side edges. The side edges are substantially straight and converging toward the trailing edge. Thus the trailing edge is shorter than the leading edge. Both the leading and trailing edges have a plurality of alternating straight lines and arcs, the opposite lines being parallel and the opposite arcs being concentric.

A container body formed from this blank has articulated walls and a side seam between two articulations, the articulations being arcuate. Each of the walls is straight and tapered inwardly toward the bottom; and the bottom end is closed by means of an end closure secured to the body. The opposite end of the container is ICC open and has a perimeter longer than the perimeter at'the bottom end.

Referring to the drawings:

FIG. 1 is a plan view of a body blank embodying the principles of this invention;

FIG. 2 is a perspective view of the container made from the body blank shown in FIG. l;

FIG. 3 is a sectional view taken substantially along line` 3 3 of FIG. 2;

FIG. 4 is an enlarged fragmentary sectional view taken substantially along line 4 4 of FIG. 2; and

FIG. 5 is an enlarged fragmentary sectional view taken substantially along line S--S of FIG. 2.

As a preferred or exemplary embodiment of the instant invention, FIG. l shows a fibre blank,l generally designated 10, having side edges 12 and 14, which are substantially straight. lBoth side edges 12 and 14 intersect a leading edge 16 and a trailing edge 18. The leading edge 16 is longer than the trailing edge 18. Thus the side edges 12 and 14 converge lfrom the leading edge 16 to the trailing edge 18.

Each of the leading and trailing edges have a plurality of alternating straight lines '20, 21 and arcs 22, 23. The lines 20 in the leading edge 16 and the lines 21 in the trailing edge 18 are parallel to each other, while the opposite arcs 22 and 23 on the leading edge 16 and the trailing edge 18 respectively are concentric. These alternate straight lines and arcs allow formation of a tapered container body wherein both the top and bottom ends lie in two substantially parallel planes, which will be more fully described hereinafter.

A corner 24 is cut from the leading edge 16 in orderr to allow the formation of a top bead in the finished container without an uneven edge.

Spaced from and adjacent to the trailing edge 18 is a` long score line 26 which comprises a plurality of alternate;

straight lines 28 and arcs 30. These are respectively parallel and concentric to their opposite lines 21 and arcs 23 in the trailing edge 18 and deiine a band 31. In addition, a plurality of short score lines 32 intersect each arc 23 and terminate at the arc 30 of the score line 26. Each of these short score lines 32 is substantially normal tothat' portion of the edge 18 and the score line 26 with which they intersect. These scored lines facilitate bending and formation of a container from theblank 10, which will'be explained more fully hereinafter. i l

FIGS. 2, 3, 4 and 5 show a disposable tapered con-l tainer, generally designated 34, Whose body 36 is formed from the blank 10. The container 34 comprises a tapered, substantially rectangular body 36 having a side seam 38 which is adhesively sealed. The body 36 itself has a plurality of straight articulated walls 40 which are substantially at and tapered toward the bottom of the container. body 36. Each of the articulations 42 joining the walls 40 are arcuate in shape. The radius of the articulations 42 may be either smaller or larger than that shown with. out departing from the scope of the invention.

amasar At the upper end of the body wall 49 Vimmediately below the bead 52 is a substantially straight flared segment 54. This segment 54 results from formation of the bead 52. As the bead 52 is formed, the open end of the tapered cup 34 slides into engagement with the forming tool. Since the internal cross-section of the cup 34 decreases from top to bottom, the tool tends to flare the upper end of the body as the bead 52 is curled. This tlare may be eliminated, if desired, by an appropriate change in the body forming apparatus.

The interior surface of the container 34 is coated with a covering 55. The exterior surface of the walls 46 and articulations 42 are also coated with a covering 56. Preferably both interior and exterior coverings S and 56 are inert and impermeable to both hot and cold comestibles, although it can be readily understood that the inertness and impermeability of the covering is more important on the interior, being in direct contact with the containers contents, than the exterior of the container 34. Examples of such coverings are thin metals such as metal foil or vapor deposited metal; cellulosic liners such as glassine, parchment, cellophane, etc.; resinous coatings applied either as a film, such as polyethylene, polypropylene, polystyrene, etc., or as a hardenable liquid, such as cured epoxy resin, vinyl solution, etc.; and flexible ceramic coatings. Because of their chemical resistance, low cost, and ease of application, the preferred coatings are polymers of ethylenically unsaturated monomers such as polyethylene, polypropylene, polystyrene, etc.

The coverings 55 and 56 may be applied at a lamination to the fibre sheet stock, prior to the fabrication of the container, or may be applied to the ccntainer surfaces after it is fabricated. In the preferred embodiment of the invention, the coverings 5S and 56 are lms of polyethylene laminated to the fibre sheet stock from which the blank and bottom 44 are made. A polyethylene film thickness of one-half to three mils is suitable, with a preferred thickness of three-quarters to one mil. The polyethylene also acts as the adhesive for sealing the side seam 3S and end seam 5t) by the application of heat and pressure.

In manufacturing the container 34 from the blank 10 and the bottom 44 any of several means of known cupforming machinery that handle single piece blanks may be used. In forming the body 36 the blank 10 may be wrapped around a mandrel having the general shape of the finished cup body 36. Thereafter the side seam 38 is sealed by suitable means such as the application of heat. Then the bottom 44 is affixed to the lower end of the body 36. In the past when conical containers or cups were made there was complete symmetry around the periphery of the bottom. In the present design, due to the substantially rectangular shape of the container 34, such is not true. This introduces certain problems inrclosing one end of the body which are not present in conical containers.

In attaching the bottom 44 to the body 36 the skirt 48 surrounding the bottom panel 46 is positioned in the lower opening of the body 36 so that the straight score lines 28 coincide with the straight sections of the bottom panel 46 while the scored arcs 30 abut the arcuate corners of the panel 46. Then the band 31 along the trailing edge 18, of what is now the body 3d, is folded over the skirt 48 and sealed thereto by means such as heat sealing or by gluing if the thermoplastic coverings 5S and 56 are not utilized.

While securing the bottom 44 to the body 36 the short score lines 32 allow the band 31 to conform to the arcuate shape of articulations 42 in the body 36. There is thus no gathering of the band 31 fibre as the band conforms to and adheres to the curved portions of the 'skirt 48.

When the top peripheral bead 52 is made, after the body 36 is formed, it is naturally important that the bead 52 should lie in substantially a single plane. After forming the body 36 from the blank 10 and securing the bottom 44 to the lower end of the body, the bead S2 is curled in the top of the container. This top edge was the leading edge 16 in the blank 10, and comprises the alternate straight lines 20 and arcs ZZ. The straight lines 29 Vform the tops of the walls 40, while the arcs 22 form the tops of the arcuate articulations 42. The arcs 22 greatly facilitate the rolling of the upper end of the body 36 into the` bead 52, and insure its uniformity; and also insure the uniplanar disposition of the brim 53.

It is thought that the invention and many of its attendant advantages will be understood from the foregoing description and it will be apparent that various changes may be made in the form, construction and arrangement of the parts without departing from the spirit and scope of the invention or sacrificing all of its material advantages, the form hereinbefore described being merely a preferred embodiment thereof.

We claim:

l. A blank for a nestable container, polygonal in transverse cross-section comprising: a fibre sheet having side edges and a leading and trailing edge extending between said side edges; said side edges being substantially straight and converging. toward said trailing edge, whereby said trailing edge is shorter than said leading edge; each of said leading and trailing edges having a plurality of alternating straight lines and arcs, said straight lines being parallel and opposite, and'said arcs being concentric and opposite, said leading edge adapted to be curled to form a peripheral bead surrounding the mouth of the container and the said trailing edge adapted to to be turned inwardly to secur a bottom to said container.

2. The blank as set forth in claim l wherein at least one side of said sheet is coated with a polymer of an ethylenically unsaturated monomer.

3. A blank for a nestable container, polygonal in transverse cross-section comprising: a fibre sheet having side edges and a leading and trailing edge extending between said side edges; said side edges being substantially straight and converging toward said trailing edge, whereby said trailing edge is shorter than said leading edge; each of said leading and trailing edges having a plurality of alternating straight lines and arcs, said straight lines being parallel and opposite, and said arcs being concentric and opposite; and a score line adjacent said trailing edge and spaced therefrom, whereby in the finishedl container said leading edge is curled to form a peripheral bead surrounding the mouth of the container and the said trailing edge is turned inwardly to secure a bottom to said container.

4. The blank as set forth in claim `3 wherein said score line along its entire length is equally spaced from said trailing edge.

5. A blank for a nestable container, polygonal in trans- Y verse cross-section comprising: a libre sheet having side edges and a leading and trailing edge extending between said side edges; said side edges being substantially straight and converging toward said trailing edge, whereby said trailing edge is shorter than said leading edge; each of said leading and trailing edges having a plurality of alternating straight lines and arcs, said straight lines being parallel and opposite, and said arcs being concentric and opposite; a long score line adjacent said trailing edge and spaced therefrom; and a plurality of short score lines extending from said long score line to the arcs in said trailing edge, whereby in the finished container said leading edge is curled to form a peripheral bead surrounding the mouth of the container and the saidV trailing edge is turned inwardly to secure a bottom to said container.

6. The blank set forth in claim l having additionally a plurality of score lines extending from each arc in said trailing edge a short distance toward said leading edge.

7. A blank for a nesta'ole container, polygonal in transverse cross-section, comprising: a bre sheet having side edges and a leading and traiiing edge extending between said side edges; said side edges being substantially straight and converging toward said trailing edge, whereby said trailing edge is shorter than said leading edge; and each of said leading and trailing edges havinga plurality of alternating substantially opposed straight lines and arcs,

UNITED STATES PATENTS Y Ben Dec. 7, 1943 Hin oct. 23, 1956 Amberg Dec. 17, 1957 Gallagher Sept. 23, 1958 FOREIGN PATENTS Francel Feb. 7, 1906 

1. A BLANK FOR A NESTABLE CONTAINER, POLYGONAL IN TRANSVERSE CROSS-SECTION COMPRISING: A FIBRE SHEET HAVING SIDE EDGES AND A LEADING AND TRAILING EDGE EXTENDING BETWEEN SAID SIDE EDGES; SAID SIDE EDGES BEING SUBSTANTIALLY STRAIGHT AND CONVERGING TOWARD SAID TRAILING EDGE, WHEREBY SAID TRAILING EDGE IS SHORTER THAN SAID LEADING EDGE; EACH OF SAID LEADING AND TRAILING EDGES HAVING A PLURALITY OF ALTERNATING STRAIGHT LINES AND ARCS, SAID STRAIGHT LINES BEING PARALLEL AND OPPOSITE, AND SAID ARCS BEING CONCENTRIC AND OPPOSITE, SAID LEADING EDGE ADAPTED TO BE CURLED TO FORM A PERIPHERAL BEAD SURROUNDING THE MOUTH OF THE CONTAINER AND THE SAID TRAILING EDGE ADAPTED TO TO BE TURNED INWARDLY TO SECUR A BOTTOM TO SAID CONTAINER. 